JP2018091376A - Drum type shift device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drum type shift device capable of attaining simplification and downsizing of a structure for making a parking state appear.SOLUTION: A drum type shift device comprises: a parking actuation arm including an engaging part that can be engaged with a parking uneven part of a parking member, and being capable of taking a parking position where the engaging part is engaged with the parking uneven part around an oscillation axis and the parking member is forcibly brought into rotation stop state; a parking cancel spring which energizes the parking actuation arm in a parking cancel direction around the oscillation axis; and a parking push member including a main body part which is supported by the drum member, and a cam push part which extends radially outwards from the main body part. The cam push part pushes the parking actuation arm towards the parking position against an energizing force of the parking cancel spring in response to a rotating operation of the drum member to the parking position.SELECTED DRAWING: Figure 13

Description

  The present invention relates to a drum-type transmission.

  A drum-type transmission has been proposed as a transmission used for a traveling system transmission path in a working vehicle such as a utility vehicle or a tractor (see Patent Document 1 below).

  The conventional drum-type transmission described in Patent Document 1 includes a transmission gear that is supported by a first transmission rotation shaft so as to be relatively rotatable, a non-rotatable support that is supported by a second transmission rotation shaft, and directly on the transmission gear. Alternatively, a transmission gear that is indirectly meshed, a shifter member that is supported so as not to rotate relative to the first transmission rotation shaft and to be movable in the axial direction, and a drum member that has a fork guide groove and is rotated around the axis. A fork shaft parallel to the drum member, a boss portion supported by the fork shaft so as to be movable in the axial direction, an engagement pin portion engaged with the fork guide groove, and a fork portion engaged with the shifter member And a shift fork.

Specifically, a shift uneven portion is provided on the opposed end surfaces of the shifter member and the transmission gear.
By rotating the drum member around the axis, the shift fork whose axial position is regulated by the fork guide groove is moved in the axial direction, and the shifter member is engaged with the transmission gear in an uneven manner.
As a result, the gear train including the transmission gear and the transmission gear is in a power transmission state, and the power transmission between the first and second transmission rotating shafts is performed at the gear ratio of the gear train.

By the way, it is desired that the drum-type transmission device be exposed to a parking state where the rotation is forcibly stopped in addition to the power transmission state by the gear train.
In this regard, in addition to the above-described configuration, the conventional drum-type transmission includes a parking gear supported so as not to rotate relative to the first transmission rotation shaft, and a rotation operation of the drum member to the parking position around the axis. Accordingly, a parking lock mechanism for forcibly stopping the rotation of the parking gear is provided.

  The parking lock mechanism includes a locking member provided on the drum member, and a plate in which a recess into which the locking member can enter is formed, and the drum member rotates around the axis to the parking position. Then, the locking member enters the recess to swing the plate, and the parking gear is locked using the swing of the plate.

  The conventional drum-type transmission is useful in that the parking state can be revealed while eliminating the need for a dedicated actuator for revealing the parking state, but the configuration of the parking lock mechanism is complicated, There is a problem in that the entire apparatus including the parking lock mechanism is increased in size and cost.

Japanese Patent No. 5909400

  The present invention has been made in view of the above-described prior art, and is a drum-type transmission capable of selectively displaying a power transmission state and a parking state, and a simplified structure for revealing the parking state and An object of the present invention is to provide a drum-type transmission that can be miniaturized.

  In order to achieve the above object, the present invention provides a transmission gear that is supported by a first transmission rotation shaft so as to be relatively rotatable, and a second transmission rotation shaft that is supported so as not to be relatively rotatable and directly or indirectly by the transmission gear. A transmission gear meshed with each other, a parking concavo-convex portion, a parking member which is not rotatable relative to the first or second transmission rotating shaft, and a relative rotation impossible to the first transmission rotating shaft and axial movement. A shifter member that is supported, a drum member that has a fork guide groove and is rotated around an axis, a fork shaft parallel to the drum member, and a state in which the axial position is guided by the fork guide groove And a shift fork that is supported by the fork shaft so as to be movable in the axial direction and moves the shifter member in the axial direction in accordance with the movement in the axial direction of the fork shaft. Has a concavo-convex portion for shifting on opposite end surfaces with respect to each other, and the shift fork is moved in the axial direction together with the shifter member via the fork guide groove according to the rotation of the drum member, so that the shifter member is A drum-type transmission that engages with a gear and has an engaging portion that can be engaged with the parking uneven portion, and is capable of swinging about a swing axis parallel to the transmission rotation shaft. An operating arm for parking, which can take a parking position around the swing axis so that the engaging portion is engaged with the uneven portion for parking and forcibly stops the parking member. , Parking release for urging the operating arm for parking around the swing axis in a parking release direction for separating the engaging portion from the uneven portion for parking And a parking pressing member having a main body portion supported by the drum member and a cam pressing portion extending radially outward from the main body portion, wherein the cam pressing portion is the drum When the member is positioned at the neutral position and the shift position, it does not act on the parking operation arm, and resists the biasing force of the parking release spring according to the rotation of the drum member to the parking position. And providing a drum-type transmission that pushes the parking operating arm toward the parking position.

Preferably, the main body portion is supported by the drum member so as to be relatively rotatable, and is operatively connected to the drum member via a parking coil spring that is externally attached to the drum member.
When the circumferential load applied to the cam pushing portion is a predetermined value or less, the parking coil spring integrally rotates the parking pushing member around the axis along with the rotation of the drum member around the axis. When the circumferential load applied to the cam pushing portion exceeds a predetermined value, the drum member is elastically deformed and the drum member rotates about the axis with respect to the parking pushing member. Is configured to allow relative rotation in advance.
When the cam actuating portion swings the parking actuating arm toward the parking position, the engaging portion of the parking actuating arm is abutted against the convex portion of the parking gear concavo-convex portion, and the cam pushing operation is performed. When a circumferential load exceeding the predetermined value is applied to the part, the drum member rotates relative to the parking push member to the parking operation position while elastically deforming the parking coil spring, and the engaging part and At the stage where the circumferential position of the parking uneven portion is aligned, the holding elasticity of the parking coil spring resists the biasing force of the parking release spring and swings the parking operating arm to the parking position. The engagement between the joint portion and the parking uneven portion is completed.

  The operating arm for parking has a pressure receiving surface with which the cam pushing portion is engaged, and preferably, the cam pushing portion moves the cam from the pressure receiving surface when the operating arm for parking is positioned at a parking position. The direction of the reaction force received by the pushing portion is arranged so as to be substantially opposed to the direction in which the cam pushing portion extends radially outward with respect to the axis of the drum shaft.

  Preferably, in a state where the cam pushing portion does not act on the parking operation arm, the parking operation arm that is biased in the release direction around the swing axis by the parking release spring comes into contact with the fork shaft. The oscillating end of the parking actuating arm in the releasing direction around the oscillating axis is defined.

  In one form, the said shifter member shall have the said uneven | corrugated part for parking in the outer peripheral surface which faces a radial direction outward, and the said shifter member is comprised so that it may act also as the said parking member.

  In another embodiment, the parking member is formed separately from the shifter member, and is formed by a parking gear supported on the first or second transmission rotation shaft so as not to be relatively rotatable.

Preferably, the operating arm for parking includes a boss portion that is externally rotatably attached to a pivot shaft that defines the swing axis, and extends radially outward from the boss portion and engages with the distal end side. And an arm portion having a portion.
The parking release spring includes a coil spring that is externally attached to a boss portion of the parking operation arm. The coil spring has one end locked to the pivot shaft and the other end connected to the parking operation arm. Locked.

Preferably, the drum-type transmission according to the various configurations may include a shift fork pushing spring that biases the shift fork in a direction in which the shifter member is pressed against the transmission gear.
When the shift fork and the shifter member are positioned at the reference position and the shift position when the shifter member is not engaged with the shift gear and when the shift gear is engaged with the shift gear, respectively. The fork guide groove holds the shift fork at the reference position when the drum member is positioned at the neutral position and the parking position around the axis, and the drum member is positioned at the shift position around the axis. In some cases, the shift fork has a groove shape for guiding the shift fork so that the shift fork can move in the axial direction between the reference position and the shift position.

  The drum-type transmission according to the present invention has an engaging portion that can be engaged with the parking uneven portion of the parking member, and the engaging portion is engaged with the parking uneven portion around the swing axis. A parking operation arm that can take a parking position that forces the parking member to stop rotating, a parking release spring that urges the parking operation arm in the parking release direction around the swing axis, and the drum And a parking push member having a cam push portion extending radially outward from the main body portion, the cam push portion having a neutral position when the drum member is When it is in the shift position, it does not act on the parking operating arm, and the parking release spring is operated in response to the rotation of the drum member to the parking position. Because against the force are configured to push towards the actuating arm parking to the parking position, it is possible to simplify and miniaturize the structure for causing to appear a parking state.

FIG. 1 is a side view of a transmission to which a drum-type transmission according to a first embodiment of the present invention is applied. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and a part thereof is shown in a developed state. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 1, and shows a neutral state of the drum-type transmission. FIG. 5 is a development view of the drum member provided in the drum-type transmission according to the first embodiment, and shows a state in which the drum member is positioned at the neutral position. FIG. 6 is a cross-sectional view of the same cross section as FIG. 4 and shows a standby state in the speed change operation to the high speed gear. FIG. 7 is a development view showing a state where the drum member is positioned at a high speed position. FIG. 8 is a cross-sectional view of the same cross section as FIG. 4 and shows a standby state in the speed change operation to the low speed gear. FIG. 9 is a development view showing a state where the drum member is positioned at a low speed position. FIG. 10 is a cross-sectional view of the same cross section as that of FIG. 4 and shows a standby state in the speed change operation to the reverse gear. FIG. 11 is a development view showing a state where the drum member is positioned at the reverse movement position. FIG. 12 is a development view of a modified example of the drum member shown in FIG. 5 and shows a state in which the drum member is positioned at the neutral position. 13 is a cross-sectional view taken along line XIII-XIII in FIG. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 4 and shows a neutral state. FIG. 15 is a cross-sectional view of the same cross section as FIG. 14 and shows a reverse gear engagement state. FIG. 16 is a cross-sectional view of the same cross section as FIG. 14 and shows a parking stage engagement state. 17 is a cross-sectional view of the same cross section as FIG. 4 and shows a parking stage engagement state. FIG. 18 is a development view showing a state where the drum member is positioned at the parking position. FIG. 19 is a cross-sectional view of the same cross section as FIG. 14 and shows a standby state in the shifting operation to the parking stage. 20 is a cross-sectional view of a drum-type transmission according to a modification of the first embodiment, and shows a cross section corresponding to FIG. FIG. 21 is a cross-sectional view of the drum-type transmission according to Embodiment 2 of the present invention, showing a neutral state. FIG. 22 is a development view of a drum member provided in the drum-type transmission according to the second embodiment, and shows a state in which the drum member is positioned at a neutral position. FIG. 23 is a development view of a modified example of the drum member shown in FIG. 22 and shows a state where the drum member is positioned at the neutral position.

Embodiment 1
Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows a side view of a transmission 800 provided with a drum-type transmission 1A according to the present embodiment.
2 to 4 are sectional views taken along lines II-II, III-III and IV-IV in FIG. 1, respectively.
FIG. 2 shows the following sub output shaft 850 in a developed state.

  The drum-type transmission 1A is preferably used for a traveling system transmission path of a working vehicle such as a tractor or a utility vehicle.

  The drum-type transmission device 1A can transmit transmission of rotational power between the first and second transmission rotations 810 and 820 shafts.

  Specifically, as shown in FIGS. 1 to 4, the drum-type transmission 1 </ b> A is not relatively rotatable with respect to the transmission gear 10 that is rotatably supported by the first transmission rotation shaft 810 and the second transmission rotation shaft 820. And a transmission gear 20 that is directly or indirectly meshed with the transmission gear 810, and a drum-type transmission operation mechanism 100A that selectively places the transmission gear 20 in a power transmission state.

  In the present embodiment, the transmission gear 10 has a transmission gear 10H for forward high speed, a transmission gear 10L for forward low speed, and a transmission gear 10R for reverse travel, and the transmission gear 20 A transmission gear 20H meshing with the gear 10H and forming a forward high-speed gear train with the transmission gear 10H, a transmission gear 20L meshing with the transmission gear 10L and forming a forward low-speed gear train with the transmission gear 10L, and the transmission A transmission gear 20 </ b> R that meshes with the gear 10 </ b> R via a reverse idle gear 15 (see FIG. 3) and forms a reverse gear train together with the transmission gear 10 </ b> R and the reverse idle gear 15.

  In the present embodiment, the second transmission rotating shaft 820 acts as a speed change input shaft for operatively inputting rotational power from a drive source (not shown) such as an engine, and the first transmission rotating shaft 810. Acts as a speed change output shaft for outputting the rotational power after speed change to the drive wheels.

  That is, as shown in FIGS. 1 and 2, the transmission 800 is configured to rotate around the transmission case 805 and the transmission case 805 with one end extending outwardly so as to be operatively connected to the drive source. The second transmission rotation shaft 820 that is rotatably supported and acts as a transmission input shaft, the first transmission rotation shaft 810 that is rotatably supported about the axis of the transmission case 805 and acts as a transmission output shaft, and the first 2, the drum type transmission 1 </ b> A that transmits the rotational power from the transmission transmission shaft 820 to the first transmission rotation shaft 810 in multiple stages.

  As shown in FIGS. 1 and 2, the transmission 800 further receives rotational power that is operatively input from a pair of left and right main output shafts 840 and the speed change output shaft (the first transmission rotary shaft 810). A differential gear device 830 that differentially transmits to a pair of left and right main output shafts, and a sub output shaft 850 that outputs rotational power of the speed change output shaft to a transmission path different from the main output shaft 840 are provided.

  When the transmission 800 is applied to a traveling system transmission path of a work vehicle, for example, the pair of main output shafts 840 act as a pair of left and right rear wheel drive shafts, and the sub output shaft 850 acts as a front wheel drive shaft. Can be made.

  The drum-type speed change operation mechanism 100A is configured to selectively bring the plurality of speed change gears 20 into a power transmission state and bring the speed change device 1A into a desired gear position engagement state.

  Specifically, as shown in FIGS. 2 to 4, the speed change operation mechanism 100 </ b> A is supported by the first transmission rotation shaft 810 so as not to be relatively rotatable and axially movable, and is selected by the speed change gear 820 by axial movement. Shifter member 110 that engages in a concave-convex manner, a fork shaft 120 parallel to the first transmission rotation shaft 810, a shift fork 130 supported on the fork shaft 120 so as to be movable in the axial direction, and the first transmission rotation shaft And a drum member 140 that is rotated around an axis parallel to 810.

  Specifically, shift uneven portions 112 and 12 are respectively provided on the opposed end surfaces of the shifter member 110 and the transmission gear 10, and the shifter member 110 is axially moved in a direction close to the transmission gear 10. Accordingly, the shift uneven portion 112 of the shifter member 110 is engaged with the shift uneven portion 12 of the transmission gear 10, so that the transmission gear 10 is moved through the shifter member 110 to the first position. 1 It becomes the power transmission state which rotates integrally with the transmission rotating shaft 810.

  As shown in FIGS. 2 to 4, in the present embodiment, the first transmission rotating shaft 810 includes a transmission gear 10 </ b> H, a transmission gear 10 </ b> R, and a transmission gear 10 </ b> L in order from the first side to the second side in the axial direction. Is arranged.

  The shift operation mechanism 100A is supported as the shifter member 110 so as to be relatively non-rotatable and movable in the axial direction between the transmission gear 10H and the transmission gear 10R. The first shifter member 110 (1) that engages with the transmission gear 10H and the transmission gear 10R in accordance with the movement toward the second side, and the first transmission rotating shaft 810 cannot rotate relative to the first transmission rotation shaft 810 at a position facing the transmission gear 10L. The second shifter member 110 is supported so as to be movable in the axial direction and engages with the transmission gear 10L in a concave-convex manner in accordance with movement toward the side close to the transmission gear 10L in the axial direction (in the illustrated form, the first axial direction side). (2).

  The first shifter member 110 (1) has a high-speed concavo-convex portion 112H that can be engaged with the concavo-convex portion 12H of the transmission gear 10H on the first axial end facing the transmission gear 10H. In addition, a reverse concavo-convex portion 112 </ b> R that can be engaged with the shift concavo-convex portion 12 </ b> R of the transmission gear 10 </ b> R is provided on the end surface on the second axial side facing the transmission gear 10 </ b> R.

  The second shifter member 110 (2) has a low-speed concavo-convex portion 112L that can engage with the shift concavo-convex portion 12L of the transmission gear 10L on the first axial end surface facing the transmission gear 10L. Yes.

  Further, as shown in FIG. 4, the shift operation mechanism 100 </ b> A has first and second shift forks 130 that move the first and second shifter members 110 (1) and 110 (2) in the axial direction, respectively. Two shift forks 130 (1) and 130 (2) are provided.

  As shown in FIG. 4 and the like, the first shift fork 130 (1) is formed on the drum member 140 and the first boss portion 132 (1) supported by the fork shaft 120 so as to be movable in the axial direction. The first fork guide groove 142 (1) has a first engagement pin portion 134 (1) and a first fork portion 136 (1) engaged with the first shifter member 110 (1). The first shifter member 110 (1) is moved in the axial direction on the first transmission rotating shaft 810 in accordance with the movement in the axial direction on the fork shaft 120.

More specifically, the first shift fork 130 (1) and the first shifter member 110 (1) are axially positioned, and the first shifter member 110 (1) is uneven with respect to both the transmission gear 10H and the transmission gear 10R. A non-engaging reference position, a high speed position at which the first shifter member 110 (1) engages with the transmission gear 10H, and a reverse position at which the first shifter member 110 (1) engages with the transmission gear 10R. Can take.
FIG. 4 shows a state in which the first shift fork 130 (1) and the first shifter member 110 (1) are located at a reference position.

  The second shift fork 130 (2) includes a second boss portion 132 (2) supported by the fork shaft 120 so as to be movable in the axial direction, and a second fork guide groove 142 (2) formed in the drum member 140. ) And a second fork portion 136 (2) engaged with the second shifter member 110 (2), and the fork The second shifter member 110 (2) is moved in the axial direction on the first transmission rotating shaft 810 in accordance with the axial movement on the shaft 120.

Specifically, the second shift fork 130 (2) and the second shifter member 110 (2) are related to the axial position, and the reference position where the second shifter member 110 (2) does not engage with the transmission gear 10L. In addition, the second shifter member 110 (2) can be at a low speed position where the gear shift gear 10L is engaged with the concave and convex portions.
FIG. 4 shows a state in which the second shift fork 130 (2) and the second shifter member 110 (2) are located at a reference position.

The drum member 140 is rotated about an axis in accordance with a speed change operation.
In the present embodiment, as shown in FIG. 4, the drum-type shift operation mechanism 100 </ b> A is provided with an operation shaft 150 that receives a shift operation, and the drum member 140 is operatively connected to the operation shaft 150. ing.
In the present embodiment, the operation shaft 150 is operatively connected to the drum member 140 via a speed increasing gear train 155.

The operation shaft 150 is supported by a housing (a mission case 805 in the present embodiment) so as to be rotatable about an axis with one end portion extending outward.
As shown in FIGS. 1 and 4, the operation shaft 150 is rotated around the axis by an electric motor 155, for example.
In this case, an angle sensor 156 for detecting the position around the axis of the drum member 140 is provided.

  Alternatively, the operation shaft 150 can be rotated around the axis by human operation. In this case, the electric motor 155 is removed, and an operation arm (not shown) is attached to one end of the operation shaft 150.

  As shown in FIG. 4, the drum member 140 includes a drum body 141 in which fork guide grooves (in the present embodiment, the first and second fork guide grooves 142 (1) and 142 (2)) are formed. And a drum shaft 148 that supports the drum body 141 coaxially with the drum body 141.

  As shown in FIG. 4, the drum-type speed change operation mechanism 100A further includes a first shift fork pushing spring 160 (1) that pushes the first boss portion 132 (1) toward the first axial direction. The first boss portion 132 (1) includes a slider member 170 that is externally supported so as to be movable in the axial direction, and a slider member pushing spring 180 that pushes the slider member 170 toward the second side in the axial direction. .

  When the first shift fork 130 (1) is in a free state, the first shift fork pushing spring 160 (1) reaches the high speed position where the first shifter member 110 (1) engages with the transmission gear 10H. The first boss portion 132 (1) is set to be pushed toward the first side in the axial direction with an urging force that can be moved.

  Specifically, the first shift fork pushing spring 160 (1) has a second end portion in the axial direction as a fixed end portion that is engaged with an engaging member 126 provided on the fork shaft 120, and The end portion on the first axial side is a movable end portion engaged with the end surface on the second axial side of the first boss portion 132 (1).

  The slider member 170 is axially disposed on the first boss portion 132 (1) in a state where a moving end toward the second axial direction is defined by a stop portion 133 provided on the first boss portion 132 (1). Further, the position in the axial direction is regulated by a slider guide groove 144 provided in the drum member 140 so as to be movable.

  Specifically, the slider member 170 includes a slider main body 172 externally inserted in the first boss portion 132 (1) so as to be movable in the axial direction, and a slider engagement pin portion 174 engaged in the slider guide groove 144. have.

  The slider member pushing spring 180 is configured to push the slider member 170 toward the second side in the axial direction with a larger biasing force than the first shift fork pushing spring 160 (1).

  That is, the slider member pushing spring 180 moves the first shift fork 130 (1) to the first axial side when the first shift fork 130 (1) and the slider member 110 (1) are free. With an urging force that can move the first shifter member 110 (1) to the reverse movement position that engages with the transmission gear 10R against the urging force of the urging first shift fork pushing spring 160 (1). The first boss portion 132 (1) is set to be pushed to the second side in the axial direction through the slider member 170.

  Specifically, the slider member pushing spring 180 has a first axial end that is a fixed end locked by a locking member 127 provided on the fork shaft, and an axial second side. The end portion of the slider member 170 is a movable end portion engaged with the end surface on the first axial side of the slider member 170.

  In the present embodiment, as shown in FIG. 4, the drum-type speed change operation mechanism 100A further includes the second boss in the direction in which the second shifter member 110 (2) is pressed toward the speed change gear 10L. A second shift fork pushing spring 160 (2) for pushing the portion 132 (2) is provided.

  As described above, in the present embodiment, the transmission gear 10L is located on the first axial side of the second shifter member 110 (2), and accordingly, the second shift fork pushing spring 160 (2). Pushes the second boss 132 (2) toward the first side in the axial direction.

  Specifically, the second shift fork pushing spring 160 (2) has an end portion on the second side in the axial direction as a fixed end portion engaged with an engaging member 128 provided on the fork shaft 120, and The end portion on the first axial side is a movable end portion engaged with the end surface on the second axial side of the second boss portion 132 (2).

  When the second shift fork 130 (29) is free, the second shift fork pushing spring 160 (2) is moved to a low speed position where the second shifter member 110 (2) engages with the transmission gear 10L. The second boss portion 132 (2) is set to be pushed by an urging force that can be moved.

Here, the shape of the first fork guide groove 142 (1), the second fork guide groove 142 (2), and the slider guide groove 144 will be described.
FIG. 5 shows a development view of the drum member 140.

  The drum member 140 is configured to take an operation position around an axis corresponding to a shift stage (including a neutral stage) that the drum type transmission 1A can take.

  In the present embodiment, the drum-type transmission 1A is configured to be able to take a neutral stage, a forward high speed stage, a forward low speed stage, and a reverse stage, and thus the drum member 140 is configured around the axis line. A neutral position N, a high speed position H, a low speed position L, and a reverse position R are configured.

  Specifically, in the present embodiment, the drum member 140 assumes a high speed position H when rotated from the neutral position N to one side around the axis, and low speed when rotated further from the high speed position H to one side around the axis. It is configured to take a position L and take a reverse position R when rotated from the neutral position N to the other side around the axis.

The drum type transmission 1A can further take a parking stage, and the drum member 140 can take a parking position P in addition to the operation position.
As shown in FIG. 5, in the present embodiment, the drum member 140 is configured to take the parking position P when it is further rotated from the reverse position R to the other side around the axis.
A configuration for making this parking state appear will be described later.

  As shown in FIG. 5, the first fork guide groove 142 (1), the slider guide groove 144 and the second fork guide groove 142 (2) have the drum member 140 in a neutral position N, a high speed position H, and a low speed. When positioned at the position L, the reverse position R, and the parking position P, the neutral engagement portion and the high-speed engagement are engaged with the corresponding engagement pin portions 134 (1), 174, 134 (2), respectively. It has a part, an engagement part at low speed, an engagement part at reverse travel, and an engagement part at parking.

First, the groove shape of the first fork guide groove 142 (1) will be described.
As shown in FIG. 5, the neutral engagement portion 142 (1) N of the first fork guide groove 142 (1) is fixed to the first engagement portion 142 (1) so as to fix the first shift fork 130 (1) at a reference position. It has a groove shape that holds the mating pin portion 134 (1).

  The engagement portion 142 (1) H at high speed is such that the moving end of the first shift fork 130 (1) toward the first axial direction becomes the high speed position and the moving end toward the second axial direction becomes the reference position. Further, it has a groove shape for guiding the first engagement pin 134 (1).

  The transition portion located between the neutral engagement portion 142 (1) N and the high speed engagement portion 142 (1) H is a movement end of the first shift fork 130 (1) toward the second side in the axial direction. While being fixed at the reference position, the moving end of the first shift fork 130 (1) in the first axial direction is changed from the reference position to the high speed position in accordance with the rotation from the neutral position N to the high speed position H of the drum member 140. It has such a groove shape.

  The low speed engagement portion 142 (1) L has a groove shape that holds the first engagement pin portion 134 (1) so as to fix the first shift fork 130 (1) at a reference position. Yes.

  The transition portion between the high-speed engagement portion 142 (1) H and the low-speed engagement portion 142 (1) L is the reference position of the moving end of the first shift fork 130 (1) toward the second side in the axial direction. The moving end of the first shift fork 130 (1) in the first axial direction is changed from the high speed position to the reference position in accordance with the rotation of the drum member 140 from the high speed position H to the low speed position L. It has a groove shape.

  The reverse engagement portion 142 (1) R is a groove that uses the movement end of the first shift fork 130 (1) in the axial direction first side as a reference position and the movement end in the axial direction second side as a reverse movement position. It has a shape.

  The transition part located between the neutral engagement part 142 (1) N and the reverse engagement part 142 (1) R is the movement end of the first shift fork 130 (1) toward the first side in the axial direction. While being fixed at the reference position, the moving end of the first shift fork 130 (1) in the second axial direction is changed from the reference position to the reverse position in accordance with the rotation from the neutral position N to the reverse position R of the drum member 140. It has such a groove shape.

  The parking engaging portion 142 (1) P has a groove shape for fixing the first shift fork 130 (1) to a reference position.

  The transition portion between the reverse engagement portion 142 (1) R and the parking engagement portion 142 (1) P is the reference position of the movement end of the first shift fork 130 (1) toward the first side in the axial direction. The moving end of the first shift fork 130 (1) in the second axial direction is changed from the reverse position to the reference position in accordance with the rotation from the reverse position R to the parking position P of the drum member 140. It has a groove shape.

Next, the groove shape of the slider guide groove 144 will be described.
The slider guide groove 144 is permitted by the high speed engagement portion 142 (1) H of the first fork guide groove 142 (1) when the first drum member 140 is positioned at the high speed position H. The slider member 170 is fixed at a retracted position that does not limit the axial movement range of the one shift fork 130 (1).

  Specifically, the axis on which the slider member 170 is positioned when the first shift fork 130 (1) is positioned at the reference position, the high speed position, and the reverse position while the slider member 170 is in contact with the stop portion 133. The direction positions are defined as a reference position, a first displacement position, and a second displacement position, respectively (see FIG. 5).

  In the present embodiment, as shown in FIG. 5, the high speed engagement portion 144H of the slider guide groove 144 is configured to fix the slider member 170 at the first displacement position.

  That is, in the present embodiment, the slider guide groove 144 is configured to fix the slider member 170 to the first displacement position as the retracted position when the drum member 140 is positioned at the high speed position H. Has been.

In the present embodiment, the slider guide groove 144 further has the following groove shape.
That is, as shown in FIG. 5, the neutral engaging portion 144N has a groove shape that holds the slider engaging pin portion 174 so as to fix the slider member 170 at a reference position.

  The transition portion between the neutral engagement portion 144N and the high speed engagement portion 144H guides the slider member 170 from the reference position to the first displacement position according to the rotation from the neutral position N to the high speed position H of the drum member 140. It has such a groove shape.

  The low speed engagement portion 144L has a groove shape that holds the slider engagement pin portion 174 so as to fix the slider member 170 at a reference position.

  The transition portion between the high speed engagement portion 144H and the low speed engagement portion 144L guides the slider member 170 from the first displacement position to the reference position in accordance with the rotation of the drum member 140 from the high speed position H to the low speed position L. It has such a groove shape.

  The reverse engagement portion 144R has a groove shape in which the moving end on the first axial direction side of the slider member 170 is a reference position and the moving end on the second axial direction is a second displacement position.

  The transition portion between the neutral engagement portion 144N and the reverse engagement portion 144R is fixed in the axial direction of the slider member 170 while the moving end of the slider member 170 toward the first axial direction is fixed at a reference position. The groove shape is such that the moving end to the second side is changed from the reference position to the second displacement position in accordance with the rotation from the neutral position N to the reverse position R of the drum member 140.

  The parking engaging portion 144P has a groove shape that fixes the slider member 170 at a reference position.

  The transition portion between the reverse engagement portion 144R and the parking engagement portion 144P is fixed in the axial direction of the slider member 170 while the moving end of the slider member 170 toward the first axial direction is fixed at a reference position. A groove shape is formed such that the moving end to the second side changes from the second displacement position to the reference position in accordance with the rotation from the reverse position R to the parking position P of the drum member 140.

Next, the groove shape of the second fork guide groove 142 (1) will be described.
The second fork guide groove 142 (1) allows the second shift fork 130 (2) to move in the axial direction between the reference position and the low speed position when the drum member 140 is positioned at the low speed position L. On the other hand, when the drum member 140 is positioned at an operating position other than the low speed position L, the second shift fork 130 (2) has a groove shape that fixes the reference position.

  That is, as shown in FIG. 5, the second shift fork 130 (2) is fixed at the reference position in the region from the high speed engagement portion 142 (2) H to the parking engagement portion 142 (2) P. Thus, it has a groove shape that holds the second engagement pin portion 134 (2).

  On the other hand, the low-speed engagement portion 142 (2) L has the moving end of the second shift fork 130 (2) toward the first axial direction as the low speed position and the moving end toward the second axial direction as the reference position. It has a groove shape that

  The transition portion between the high speed engagement portion 142 (2) H and the low speed engagement portion 142 (2) L is a movement end of the second shift fork 130 (2) toward the second side in the axial direction. While being fixed at the reference position, the moving end of the second shift fork 130 (2) in the first axial direction is changed from the reference position to the low speed position according to the rotation of the drum member 140 from the high speed position H to the low speed position L. It has such a groove shape.

  The drum-type shift operation mechanism 100A having such a configuration can exhibit a standby action during a shift operation.

First, the standby operation in the shifting operation to the high speed stage will be described.
When the drum member 140 is positioned at the neutral position N, as described above, the first shift fork 130 (1) and the second shift fork 130 (2) are fixed at the reference position ( (See FIG. 5).
Accordingly, the first and second shifter members 110 (1) and 110 (2) are both positioned at the reference position, and the drum-type transmission 1A is in the neutral stage (see FIG. 4).

  When the drum member 140 is operated from the neutral position N to the high speed position H, as described above, the axial direction of the first shift fork 130 (1) regulated by the first fork guide groove 142 (1). The moving end on the first side changes from the reference position to the high speed position according to the rotation from the neutral position N to the high speed position H of the drum member 140, and when the drum member 140 is positioned at the high speed position H, The shift fork 130 (1) is movable in the axial direction between the reference position and the high speed position.

  On the other hand, when the drum member 140 is positioned at the high speed position H, the slider member 170 is fixed at the retracted position (first displacement position in the present embodiment) by the slider guide groove 144.

  In this state, the force by which the slider member pushing spring 180 pushes the slider member 170 to the second axial direction does not act on the first boss portion 132 (1), and the first boss portion 132. Only the urging force to the second side in the axial direction by the first shift fork pushing spring 160 (1) acts on (1).

  Accordingly, when the drum member 140 is positioned at the high speed position H, the first shift fork 130 (1) and the first shifter member 110 (1) are attached to the first shift fork pushing spring 160 (1). It becomes a state that can be moved to a high speed position by the force.

  Here, when the drum member 140 is positioned at the high speed position H, the relative position around the axis between the high speed uneven portion 112H of the first shifter member 110 (1) and the speed change uneven portion 12H of the transmission gear 10H. Is the position where the concave and convex portions can be engaged with each other, the concave and convex portions for high speed 112H and the convex and concave portions for shifting 12H are immediately engaged with the concave and convex portions so that the transmission gear 10H is in a transmission state, and the drum-type transmission 1A immediately A step engagement state is established.

However, depending on the relative positions of the first shifter member 110 (1) and the transmission gear 10H around the axis, the projections of the high-speed irregularities 112H and the transmission gear 10H of the first shifter member 110 (1) A situation may occur in which the convex portions of the concavo-convex portion 12H are abutted against each other (see FIG. 6).
In this case, the first shifter member 110 (1) cannot immediately move to the high speed position.

  Even if such a situation occurs, in the present embodiment, the drum member 140 can be rotated in advance to the high speed position H (see FIG. 7), and then the first shift fork pushing spring 160 ( The first shift fork 130 (1) and the first shifter member 110 (1) are moved to the high speed position by the urging force of 1) to complete the shift operation to the high speed stage of the drum type transmission 1A. Can do.

  That is, when a situation occurs in which the convex portions are brought into contact with each other, the first shifter member 110 (1) and the first shift fork 130 (1) are connected to the first shift fork as shown in FIGS. In a state where the urging force toward the first axial direction by the push spring 160 (1) continues to be received, the projections are fixed at the reference position by abutment.

  Therefore, when the first shifter member 110 (1) and the transmission gear 10H rotate relative to each other around the axis line and the projections are not matched, the first shift fork pushing spring 160 (1) is attached. The first shifter member 110 (1) is pushed to the high speed position via the first shift fork 130 (1) by the force and engages with the transmission gear 10H so that the high speed of the drum type transmission 1A is high. The shift operation to the gear is completed (standby action to the high gear).

  When the drum member 140 is positioned at the high speed position H, as described above, the second shift fork 130 (2) and the second shifter member 110 (2) are fixed at the reference position, The transmission gear 10L is in a non-transmission state.

Next, the standby action in the shifting operation to the low speed stage will be described.
When the drum member 140 is positioned at the low speed position L, the second shift fork 130 (2) (and the second shifter member 110 (2)) are moved by the second shift fork pushing spring 160 (2). In a state of being biased toward the low-speed position on the second side in the axial direction, the state is movable in the axial direction between the reference position and the low-speed position.

  Here, when the drum member 140 is positioned at the low speed position L, the relative position around the axis between the low speed uneven portion 112L of the second shifter member 110 (2) and the speed change uneven portion 12L of the transmission gear 10L. , The low-speed concavo-convex portion 112L and the shift concavo-convex portion 12L immediately engage with the concavo-convex portion, and the transmission gear 10L is brought into a transmission state, so that the drum-type transmission 1A immediately becomes low-speed. A step engagement state is established.

  On the other hand, when the convex part of the uneven part for low speed 112L of the second shifter member 110 (2) and the convex part of the uneven part for shifting 12L of the transmission gear 10L are brought into contact with each other (FIG. 8), the second shifter member 110 (2) (and the second shift fork 130 (2)) receives a biasing force toward the first axial direction by the second shift fork pushing spring 160 (2). In this state, the drum is fixed at the reference position (see FIG. 8), and only the drum member 140 can be rotated to the low speed position L (see FIG. 9).

  Then, when the second shifter member 110 (2) and the transmission gear 10L rotate relative to each other around the axis and the butting of the convex portions is eliminated, the second shift fork pushing spring 160 (2) is attached. The second shifter member 110 (2) is pushed to the low speed position by the force and engages with the unevenness of the transmission gear 10L, and the shifting operation to the low speed stage of the drum type transmission 1A is completed (to the low speed stage). Standby action).

  When the drum member 140 is positioned at the low speed position L, as described above, the first shift fork 130 (1) and the first shifter member 110 (1) are fixed at the reference position, The transmission gear 10H and the transmission gear 10R are in a non-transmission state.

Next, the standby operation in the shifting operation to the reverse gear will be described.
When the drum member 140 is positioned at the reverse drive position R, the first shift fork 130 (1) is urged toward the first axial direction by the first shift fork pushing spring 160 (1). In this state, it is possible to move in the axial direction between the reference position and the reverse position.

  On the other hand, the slider member 170 is urged toward the second axial direction by the slider member pressing spring 180 and is movable in the axial direction between the reference position and the second displacement position. .

  As described above, the urging force of the slider member pushing spring 180 is larger than the urging force of the first shift fork pushing spring 160 (1), and therefore the drum member 140 is positioned at the reverse position R. In this case, the first shift fork 130 (1) is sized according to the difference between the urging force of the slider member pushing spring 180 and the urging force of the first shift fork pushing spring 160 (1). It can be moved to the reverse position on the second axial side by the urging force.

  Here, when the drum member 140 is positioned at the reverse position R, the relative position around the axis between the reverse uneven portion 112R of the first shifter member 110 (1) and the shift uneven portion 12R of the transmission gear 10R. Is the position where the concave / convex engagement is possible, the reverse concave / convex portion 112R and the shift concave / convex portion 12R immediately engage with the concave / convex portion, and the transmission gear 10R enters the transmission state, and the drum transmission 1A immediately reverses. A step engagement state is established.

  On the other hand, when a situation occurs in which the convex portion of the reverse uneven portion 112R of the first shifter member 110 (1) and the convex portion of the shift uneven portion 12R of the transmission gear 10R are brought into contact with each other, The first shifter member 110 (1) (and the first shift fork 130 (1)) has a difference between the biasing force of the slider member pushing spring 180 and the biasing force of the first shift fork pushing spring 160 (1). Accordingly, the drum member 140 is fixed to the reference position while being biased toward the second axial direction by a biasing force of a magnitude corresponding to (see FIG. 10), and only the drum member 140 can be rotated forward to the reverse position R. (See FIG. 11).

  Then, when the first shifter member 110 (1) and the transmission gear 10R rotate relative to each other around the axis and the abutment between the convex portions is resolved, the urging force of the slider member pushing spring 180 and the first The first shifter member 110 (1) is pushed to the reverse position via the first shift fork 130 (1) by the biasing force having a magnitude corresponding to the difference between the biasing force of the shift fork pushing spring 160 (1). It is moved to engage with the transmission gear 10R in a concave-convex manner, and the shift operation to the reverse gear of the drum type transmission 1A is completed (standby operation to the reverse gear).

  As described above, in the drum-type speed change operation mechanism 100A, the first shift fork push spring 160 (1) biases the first shift fork 130 (1) toward the high-speed position on the first side in the axial direction. In addition, the first shift is performed via the slider member 170 biased to the second axial direction by the slider member pushing spring 180 having a larger biasing force than the first shift fork pushing spring 160 (1). The fork 130 (1) is configured to be urged toward the reverse position on the second axial side, and the slider member pushing spring 180 is attached when the drum member 140 is positioned at the high speed position. The slider member 180 is moved by the slider guide groove 144 of the drum member 140 so that force does not act on the first shift fork 130 (1). By fixing the avoidance position, thereby revealing the standby action to the high speed stage by the biasing force of the first shift fork pusher spring 160 (1).

  When the drum member 140 is positioned at the reverse position, both the slider member pushing spring 180 and the first shift fork pushing spring 160 (1) act on the first shift fork 130 (1). In this state, the first shifter member 110 (1) and the first shift fork 130 (1) can move in the axial direction between a reference position and a reverse position, and the slider guide groove 144 of the drum member 140 and The first fork guide groove 142 (1) is formed, and thereby the standby action for the reverse gear is revealed by the difference in the urging force between the two push springs 180 and 160 (1).

  Therefore, as compared with the conventional configuration configured to obtain a standby action by moving the fork shaft itself in the axial direction, it is possible to reduce the size in the axial direction and reduce the operating force.

  In the present embodiment, the slider guide groove 144 fixes the slider member 170 to a reference position when the drum member 140 is positioned at the neutral position N, and the drum member 140 is positioned at the high speed position H. When the drum member 140 is positioned at the low speed position L, the slider member 170 is fixed at the reference position, and the drum member 140 is fixed at the reference position. Is moved in the axial direction between the reference position and the second displacement position, and when the drum member 140 is positioned at the parking position P, the slider member 170 is moved to the reverse position R. Although 170 is configured to be fixed at the reference position, the present invention is not limited to such a form.

  For example, when the drum member 140 is positioned at the high speed position H, the slider member 170 is fixed at the retracted position (for example, the first displacement position), while the drum member 140 is positioned at a position other than the high speed position H. In this case, the first shift fork 130 (1) is kept in a state where the slider member 170 biased toward the second axial direction by the slider member pushing spring 180 is in contact with the stop portion 133. It is also possible to employ a slider guide groove 145 formed to allow movement in the axial direction following the movement in the axial direction.

FIG. 12 is a development view of the drum member 140 provided with an example of the slider guide groove 145.
In the example shown in FIG. 12, the high speed engaging portion 145H of the slider guide groove 145 fixes the slider member 170 at the retracted position (for example, the first displacement position), and the neutral engaging portion 145N is at the low speed. The engagement portion 145L, the reverse engagement portion 145R, and the parking engagement portion 145P have groove shapes that allow the slider member 170 to move in the axial direction between the first displacement position and the second displacement position. Have.

  The drum-type speed change operation mechanism 100A further includes a detent mechanism 700 that locks the drum member 140 at each of the operation positions.

FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG.
As shown in FIGS. 4 and 13, the detent mechanism 700 is supported by a detent plate 710 supported by the drum member 140 so as not to rotate relative to the drum member 140, and a detent shaft 725 parallel to the drum member 140. A detent arm 720 and a detent spring 730 are provided.

The detent plate 710 has a plurality of detent recesses 712 that open radially outward and correspond to the operation positions that the drum member 140 can take.
As described above, in the present embodiment, the drum member 140 includes the neutral position N, the high speed position H that is located when the drum member 140 is operated from the neutral position N to one side around the axis, and the high speed position H is one around the axis. A low speed position L when operated to the side, a reverse position R when operated from the neutral position N to the other side around the axis, and a position when operated from the reverse position R to the other side around the axis The parking position P to be taken can be taken.

  Accordingly, the plurality of detent recesses 712 include a neutral position recess 712N, a high speed position recess 712H, a low speed position recess 712L, a reverse position recess 712R, and a parking position recess 712P.

The plurality of detent recesses 712 are arranged in the circumferential direction so that the recesses corresponding to the operation position of the drum member 140 are positioned at a detent position 715 facing the free end of the detent arm 712 around the axis. Yes.
FIG. 13 shows a state in which the drum member 140 is positioned at the neutral position N, and accordingly, the corresponding neutral position recess 712N is positioned at the detent position 715.

  More specifically, the neutral position recess 712N, the high speed position recess 712H, the low speed position recess 712L, the reverse position recess 712R, and the parking position recess 712P are respectively configured such that the drum member 140 is in the neutral position N, the high speed position H, and the low speed. When positioned at the position L, the reverse position R, and the parking position P, they are disposed at the detent position 715.

  The detent arm 720 has an engaging portion 722 that is rotatably supported by the detent shaft 725 at the base end and can be engaged with the detent recess 712 positioned at the detent position 715 at the free end. .

  In the present embodiment, the detent arm 720 has a roller that can rotate around a rotation axis parallel to the detent shaft 712 at the free end, and the roller acts as the engagement portion 722. ing.

  The detent spring 730 biases the detent arm 720 about the detent shaft 725 so that the engaging portion 722 of the detent arm 720 is pressed toward the detent recess 712 located at the detent position 715. .

  By providing the detent mechanism 700, it is possible to effectively prevent the drum member 140 from rotating unexpectedly from the operation position.

Hereinafter, the parking structure of the drum type transmission 1A will be described.
FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG.
FIG. 14 also shows an A1-A1 arrow view and an A2-A2 arrow view in FIG.

  As shown in FIGS. 4 and 14, in the drum-type transmission 1 </ b> A, the shift transmission fork (second shift fork 130 (2)) moves in the axial direction and the corresponding transmission gear (the transmission gear 10 </ b> L). The shifter member (the second shifter member 110 (2)) that brings the transmission gear into a power transmission state by engaging with the recesses and projections is provided with a parking unevenness portion 112P that faces radially outward.

  In addition, the drum-type transmission device 1A has a locking mechanism that forcibly engages the parking uneven portion 112P and forcibly stops the rotation of the shifter member (the second shifter member 130 (2)). 500 is provided.

  As described above, the drum-type transmission 1A also serves as a parking gear using the shifter member (the second shifter member 110 (2)) that engages and disengages power transmission by the corresponding transmission gear (the transmission gear 10L). Thus, the cost can be reduced by reducing the number of parts and the size in the axial direction can be reduced.

  That is, conventionally, a transmission gear that is rotatably supported by the first transmission rotation shaft, a transmission gear that is supported relatively non-rotatably by the second transmission rotation shaft, and meshed directly or indirectly with the transmission gear; A shifter member supported so as not to be rotatable relative to the first transmission rotation shaft and movable in the axial direction, a drum member rotated around the axis, a fork shaft parallel to the drum member, and an axial direction of the fork shaft A shift fork that is movably supported, and the shift fork whose axial position is regulated by a fork guide groove formed in the drum member is moved in the axial direction in accordance with the rotation of the drum member, and the shifter A member is engaged with the transmission gear in a concavo-convex manner so that power is transmitted between the first and second transmission rotation shafts via the transmission gear and the transmission gear. As a structure for obtaining a parking stage in the drum type transmission, the parking gear, which is a member different from the shifter member, is provided on the first transmission rotating shaft so as not to be relatively rotatable, and the parking gear is forcibly stopped. It was common to configure to be in a state.

  However, in this conventional configuration, the parking gear separated from the transmission gear and the shifter member is moved to the first transmission rotating shaft at a position displaced in the axial direction from the transmission gear and the shifter member. It is necessary to provide it, and the enlargement is caused in the axial direction.

  On the other hand, in the drum type transmission 1A according to the present embodiment, it is not necessary to provide a parking gear which is a separate member from the shifter member (the second shifter member 110 (2)), and therefore, the axial direction is not related. The apparatus can be reduced in size, and the cost can be reduced by reducing the number of parts by eliminating the need for a parking gear.

  As shown in FIG. 14, the lock mechanism 500 can swing about a swing axis 505 parallel to the first transmission rotation shaft 810 that supports the second shifter member 110 (2), and is provided at a free end. A parking operation arm 510 having an engagement portion 515 that can be engaged with the parking uneven portion 112P, and a parking release spring 520 that biases the parking operation arm 510 in the parking release direction around the swing axis 505 (FIG. 3) and a parking pushing member 530.

  In the parking operation arm 510, the engagement portion 515 is engaged with the parking uneven portion 112P around the swing axis 505 to force the second shifter member 110 (2) to stop rotating. The parking position to be taken and the parking release position where the engaging portion 515 is spaced radially outward from the parking uneven portion 112P can be taken.

  The parking push member 530 uses the movement of the drum member 140 about the axis to the parking position P to move the parking operating arm 510 against the biasing force of the parking release spring 520. Push toward.

  In this embodiment, as shown in FIGS. 4 and 14, the parking push member 530 includes a main body portion 532 supported by the drum member 140, and extends radially outward from the main body portion 532. And a cam pushing portion 535.

FIGS. 15 and 16 are cross-sectional views of the same cross section as FIG. 14, and show cross-sectional views in a state where the drum member 140 is positioned at the speed change position (reverse position R) and the parking position P, respectively.
FIG. 17 is a cross-sectional view of the same cross section as FIG. 4, and shows a cross-sectional view in a state where the parking stage is engaged.
FIG. 18 is a development view showing a state where the drum member 140 is positioned at the parking position P.

  As shown in FIGS. 14 and 15, the cam pusher 530 is configured to operate the parking operation arm when the drum member 140 is in a neutral position N and a shift position (reverse drive position R in the illustrated form). As shown in FIG. 16, the drum member 140 is rotated against the parking position P and resists the biasing force of the parking release spring 520 (see FIG. 3). The parking operation arm 510 is configured to push toward the parking position.

In this embodiment, as shown in FIGS. 3 and 14 to 16, the parking operation arm 510 is a boss portion that is externally rotatably attached to a pivot shaft 506 that defines the swing axis 505. 512 and an arm portion 514 extending radially outward from the boss portion 512, and the engagement portion 515 on the side of the free end portion of the arm portion 514 that faces the parking uneven portion 112 </ b> P. And a pressure receiving surface 516 with which the cam pushing portion 535 engages is provided on the side of the arm portion 514 opposite to the parking uneven portion 112P.
A reference numeral 508 in FIGS. 3 and 14 to 16 is a bushing that makes the boss portion 512 relatively rotatable with respect to the pivot shaft 506.

  In the present embodiment, as shown in FIG. 3, the idler shaft 16 that supports the reverse idle gear 15 forming the reverse gear train supports the parking operation arm 510 in a swingable manner. It is used as the shaft 506.

  As shown in FIG. 3 and the like, the parking release spring 520 has one end operatively connected to the parking operating arm 510 and the other end connected to the pivot shaft 506 (via the pin 522 in this embodiment). The coil spring is inserted into the pivot shaft 506 in the operatively connected state.

  In the present embodiment, as described above, when the drum member 140 is rotated from the neutral position N to the other side around the axis, the drum member 140 takes the reverse position R and from the reverse position R to the other side around the axis further. The parking position P is taken.

  Therefore, the cam pushing portion 535 does not engage with the pressure receiving surface 516 when the drum member 140 is positioned at the neutral position N (FIG. 14) and the reverse position R (FIG. 16), and the drum When the member 140 is rotated from the reverse position R toward the parking position P, the member 140 is engaged with the pressure receiving surface 516, and the parking operation arm 510 is moved to the parking position against the urging force of the parking release spring 520. Push toward.

  Thus, in the present embodiment, the parking push member 530 is supported by the drum member 140, and thereby, the parking member is utilized by utilizing the rotation of the drum member 140 to the parking position P. The lock mechanism 500 that pushes the operating arm 510 toward the parking position can be made compact.

  The drum-type transmission 1 according to the present embodiment further includes the following configuration in order to achieve a standby action in the shifting operation to the parking stage.

  In other words, in the present embodiment, the main body 532 of the parking push member 530 is extrapolated to the drum member 140 so as to be relatively rotatable.

  In addition, as shown in FIGS. 4 and 14 to 16, the parking push member 530 and the drum member 140 are operatively connected at one end to the parking push member 530 and at the other end ( In this embodiment, it is connected via a parking coil spring 540 externally attached to the drum member 140 in a state of being operatively connected to the drum member 140 (via a pin 542).

  When the circumferential load applied to the cam pushing portion 535 is a predetermined value or less, the parking coil spring 540 causes the parking pushing member 530 to rotate integrally with the rotation of the drum member 140 around the axis. And the drum member 140 is elastically deformed when the circumferential load applied to the cam pushing portion 535 exceeds a predetermined value, and the drum member 140 is moved against the parking pushing member 530. It is configured to allow a preceding relative rotation around the axis.

  In this embodiment, the parking coil spring 540 is configured to be elastically deformed in the diameter-reducing direction when the drum member 140 is rotated with respect to the parking push member 530 in a preceding relative rotation. .

By providing such a configuration, a standby action can be obtained in the shifting operation to the parking stage.
That is, when the cam pushing portion 535 swings the parking operation arm 510 toward the parking position in response to the rotation of the drum member 140 to the parking position P, the engagement of the parking operation arm 510 is performed. It is assumed that the portion 515 is abutted against the convex portion of the parking uneven portion 112P of the second shifter member 110 (2) and the parking operation arm 510 cannot swing to the parking position (see FIG. 19).

In this case, a circumferential load exceeding the predetermined value is applied to the cam pushing portion 535.
Accordingly, as shown in FIG. 19, the drum member 140 rotates relative to the parking push member 530 around the axis to the parking position P while elastically deforming the parking coil spring 540.

  The parking coil spring 540 in the elastically deformed state has an elastic force that urges the parking pushing member 530 in a direction to follow the drum member 140, and the engaging portion 515 and the parking unevenness When the portion 112P is aligned, the elastic force causes the parking operation arm 510 to swing to the parking position against the biasing force of the parking release spring 520, and the engaging portion 515 and the parking uneven portion. 112P engages with the concave and convex portions, and the shifting operation to the parking stage is completed (see FIG. 16).

  In the present embodiment, as shown in FIG. 16, when the cam pushing portion 535 positions the parking operation arm 510 in the parking position and the drum type transmission 1A enters the parking stage engagement state. Further, the direction of the reaction force acting on the cam pushing portion 535 from the pressure receiving surface 516 is substantially opposite to the direction in which the cam pushing portion 535 extends radially outward with respect to the axis of the drum member 140. (Hereinafter referred to as a “replacement” configuration by the cam pushing portion 535).

  By providing the “replacement” configuration by the cam pushing portion 535, it is possible to effectively release the engagement portion 515 of the parking operation arm 510 and the uneven portion 112P of the parking operation unexpectedly. It can be prevented or reduced.

  Specifically, when the drum-type transmission 1A is used for a traveling transmission path of a work vehicle, the drum member 140 is positioned at the parking position P while the work vehicle is located on a slope. Assume that the drum-type transmission 1A is in the parking stage engaged state.

  In such a situation, gravity applied to the work vehicle is reversely transmitted from the driving wheel to the first transmission rotating shaft 810, and a rotational driving force around the axis acts on the first transmission rotating shaft 810.

  In general, the concave section of the concave / convex engaging structure (in this embodiment, the concave section of the parking concave / convex section 112P) is formed in a tapered shape that becomes narrower as it goes radially inward. By making the cross-sectional view shape of the convex portion to be engaged (engagement portion 515 of the parking operation arm 510 in the present embodiment) a taper shape corresponding to the concave portion, it is possible to make the concave-convex engagement easy. Can be secured.

  On the other hand, if the concave and convex portions of the parking uneven portion 112P and the engaging portion 515 are tapered, the reverse driving force from the driving wheel is transmitted to the first transmission rotating shaft 810. This reverse driving force acts as a force for swinging the parking operation arm 510 in the parking release direction, and the parking operation arm 510 located at the parking position is unexpectedly moved in the parking release direction. As a result of swinging, the concave / convex engagement of the parking operating arm 510 and the parking concave / convex portion 112P may be released.

  In this regard, if the “replacement” configuration by the cam pushing portion 535 is provided, it is possible to effectively prevent or reduce the situation in which the parking operation arm 510 swings unexpectedly from the parking position in the release direction.

  Further, in the present embodiment, as shown in FIGS. 14 and 15, etc., the cam pushing portion 535 is not engaged with the parking operation arm 510, that is, the drum member 140 is at a low speed position. In the state where the fork shaft 120 is positioned at the operation position from L to the reverse position R, the fork shaft 120 is applied to the parking operation arm 510 urged in the parking release direction around the swing axis 505 by the parking release spring 520. It is configured to abut and define a swing end of the parking operation arm 510 in the parking release direction.

  With such a configuration, the parking release direction is set by the parking release spring 520 in a situation where the drum member 140 is positioned at the operation position between the low speed position L and the reverse drive position R without providing an additional member. The parking operating arm 510 biased toward the parking force is pressed against the parking pushing member 530, and the biasing force of the parking release spring 520 affects the operation of the drum member 140 around the axis. It can be effectively prevented.

The parking push member 530 supported by the drum member 140 and the swing axis 505 parallel to the first transmission rotation shaft 810 can swing, and the engaging portion 515 is provided at a free end. The parking operation arm 510 and a parking release spring 520 that urges the parking operation arm 510 in the release direction around the swing axis 505 are provided, and the rotation of the drum member 140 at the parking position P is utilized. The lock mechanism 500 that causes the parking operation arm 510 to swing by the parking push member 530 to reveal the parking stage engagement state is parked on the shifter member (the second shifter member 110 (2)). The present invention is not applied only to the form in which the uneven portion 112P is provided. The shifter member (the second shifter member 110 (2)) is applicable to form a dedicated parking gear 10P of another member.
FIG. 20 is a cross-sectional view of a modified example in which the lock mechanism 500 is applied to a form provided with a parking gear 10P that is a member different from the shifter member (the second shifter member 110 (2)).

Embodiment 2
Hereinafter, other embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 21 is a cross-sectional view of the drum-type transmission 1B according to the present embodiment, and shows a cross-sectional view corresponding to FIG. 4 of the first embodiment.
In the figure, the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

  The drum-type transmission 1B according to the present embodiment is different from the drum-type transmission 1A according to the first embodiment in that a drum-type transmission operation mechanism 100B is provided instead of the drum-type transmission operation mechanism 100A. doing.

  As shown in FIG. 21, the drum-type speed change operation mechanism 100B includes the first shifter member 110 (1), the second shifter member 110B (2), the fork shaft 120, the first shift fork 130 ( 1), the second shift fork 130 (2), and a drum member 140B.

  The first shifter member 110 (1) is supported on the first transmission rotating shaft 810 between the transmission gear 10H and the transmission gear 10R so as not to rotate relative to the first transmission rotating shaft 810 and to move in the axial direction. It is moved in the axial direction by 1).

  The first shifter member 110 (1) has a high-speed concavo-convex portion 112H that can be concavo-convexly engaged with the transmission concavo-convex portion 12H of the transmission gear 10H on one end face in the axial direction facing the transmission gear 10H, A reverse concavo-convex portion 112R that can engage with the concavo-convex portion for shifting 12R of the transmission gear 10R on the other end surface in the axial direction opposite to the transmission gear 10R is provided.

  The first shifter member 110 (1) and the first shift fork 130 (1) have a reference in which the first shifter member 110 (1) does not engage with either the transmission gear 10H or the transmission gear 10R in the axial direction. 21 (see FIG. 21), a high speed position at which the first shifter member 110 (1) engages with the transmission gear 10H, and a reverse position at which the first shifter member 110 (1) engages with the transmission gear 10R. And can take.

  The drum-type transmission 1B according to the present embodiment includes, as the transmission gear 10, a parking gear (transmission gear 10P) that forms a parking stage in addition to the transmission gear 10H, the transmission gear 10L, and the transmission gear 10R. Yes.

The parking gear (transmission gear 10P) is fixed to a fixing member such as the transmission case 805 so as not to rotate.
That is, in the present embodiment, the parking gear (transmission gear 10P) is a separate member from the shifter member.

  In such a configuration, the second shifter member 110B (2) is supported between the transmission gear 10L and the transmission gear 10P so as to be non-rotatable relative to the first transmission rotation shaft 810 and movable in the axial direction. It is moved in the axial direction by the two-shift fork 130 (2).

  The second shifter member 110B (2) has a low-speed concavo-convex portion 112L that can be concavo-convexly engaged with the shift concavo-convex portion 12L of the transmission gear 10L on the end surface on one side in the axial direction facing the transmission gear 10L, and A parking uneven portion 112P that can engage with the shift uneven portion 12P of the transmission gear 10P on the other end face in the axial direction facing the transmission gear 10P is provided.

  The second shifter member 110B (2) and the second shift fork 130 (2) have a reference in which the second shifter member 110B (2) does not engage with either the transmission gear 10L or the transmission gear 10P in the axial direction. 21 (see FIG. 21), a low speed position where the second shifter member 110B (2) engages with the transmission gear 10L, and a parking position where the second shifter member 110B (2) engages with the transmission gear 10P. And can take.

  As shown in FIG. 21, the drum-type speed change operation mechanism 100B further includes a first shift fork that pushes the first boss portion 132 (1) of the first shift fork 130 (1) to the second side in the axial direction. A push spring 160 (1), a second shift fork push spring 160 (2) that pushes the second boss 132 (2) of the second shift fork 130 (2) toward the first axial side, The first boss portion 132 (1) is axially moved to the first boss portion 132 (1) in a state where a moving end toward the first axial direction is defined by the first stop portion 133 (1) provided on the first boss portion 132 (1). A moving end toward the second axial direction is defined by the first slider member 170 (1) supported in a possible manner and the second stop portion 133 (2) provided in the second boss portion 132 (2). Can move axially to the second boss 132 (2) in a state A supported second slider member 170 (2), a first slider member pushing spring 180 (1) for pushing the first slider member 170 (1) to the first axial direction, and the second slider member And a second slider member pushing spring 180 (2) that pushes 170 (2) to the second side in the axial direction.

The axial position of the first slider member 170 (1) is regulated by a first slider guide groove 144B (1) provided in the drum member 140B.
That is, the first slider member 170 (1) includes a first slider body 172 (1) externally inserted in the first boss portion 132 (1) so as to be movable in the axial direction, and a first slider of the drum member 140B. And a first slider engaging pin portion 174 (1) engaged with the guide groove 144B.

The axial position of the second slider member 170 (2) is regulated by a second slider guide groove 144B (2) provided in the drum member 140B.
That is, the second slider member 170 (2) includes a second slider body 172 (2) externally inserted in the second boss portion 132 (2) so as to be movable in the axial direction, and a second slider of the drum member 140B. And a second slider engaging pin portion 174 (2) engaged with the guide groove 144B (2).

The first slider member pushing spring 180 (1) has a larger urging force than the first shift fork pushing spring 160 (1).
The second slider member pushing spring 180 (2) has a larger urging force than the second shift fork pushing spring 160 (2).

  As shown in FIG. 21, in the present embodiment, the first and second slider member pushing springs 180 (1) and 180 (2) are engaged with the first slider member 170 (1) at one end side. And the other end is formed by a single spring 210 engaged with the second slider member 170 (2).

Here, the guide groove formed in the drum member 140B will be described.
FIG. 22 is a development view of the drum member 140B.

  As shown in FIG. 22, the drum member 140B has a first fork guide groove 142B (1) into which the first engagement pin portion 134 (1) of the first shift fork 130 (1) is engaged, The second fork guide groove 142B (2) in which the second engagement portion 134 (2) of the second shift fork 130 (2) is engaged, and the first slider engagement of the first slider member 170 (1). The first slider guide groove 144B (1) in which the pin portion 174 (1) is engaged and the second slider engaging pin portion 171 (2) of the second slider member 170 (2) are engaged. A slider guide groove 144B (2) is provided.

First, the groove shape of the first fork guide groove 142B (1) will be described.
As shown in FIG. 22, the neutral engagement portion 142B (1) N of the first fork guide groove 142B (1) is fixed to the first engagement so as to fix the first shift fork 130 (1) to a reference position. It has a groove shape that holds the mating pin portion 134 (1).

  In the high speed engagement portion 142B (1) H, the moving end of the first shift fork 130 (1) in the first axial direction is the high speed position, and the moving end of the first shift fork 130 (1) in the second axial direction is the reference position. Further, it has a groove shape for guiding the first engagement pin 134 (1).

  The transition portion located between the neutral engagement portion 142B (1) N and the high speed engagement portion 142B (1) H is a movement end of the first shift fork 130 (1) toward the second side in the axial direction. The movement end of the first shift fork 130 (1) in the first axial direction is changed from the reference position to the high speed position according to the rotation from the neutral position N to the high speed position H of the drum member 140B while being fixed at the reference position. It has such a groove shape.

  The low speed engagement portion 142B (1) L has a groove shape that holds the first engagement pin portion 134 (1) so as to fix the first shift fork 130 (1) at a reference position. Yes.

  The transition portion between the high-speed engagement portion 142B (1) H and the low-speed engagement portion 142B (1) L has a movement end of the first shift fork 130 (1) in the second axial direction as a reference position. As the drum member 140B (1) rotates from the high speed position H to the low speed position N, the moving end of the first shift fork 130 (1) changes from the high speed position to the reference position. It has a groove shape.

  The reverse engagement portion 142B (1) R is such that the moving end of the first shift fork 130 (1) toward the first axial direction is the reference position and the moving end toward the second axial direction is the reverse position. Further, it has a groove shape for guiding the first engagement pin 134 (1).

  The transition portion located between the neutral engagement portion 142B (1) N and the reverse engagement portion 142B (1) R is a movement end of the first shift fork 130 (1) toward the first side in the axial direction. While being fixed at the reference position, the moving end of the first shift fork 130 (1) in the second axial direction is changed from the reference position to the reverse position according to the rotation from the neutral position N to the reverse position R of the drum member 140B. It has such a groove shape.

  The parking engagement portion 142B (1) P has a groove shape that holds the first engagement pin portion 134 (1) so as to fix the first shift fork 130 (1) to a reference position. Yes.

  The transition portion between the reverse-engagement portion 142B (1) R and the parking-time engagement portion 142B (1) P is the reference position of the moving end of the first shift fork 130 (1) toward the first side in the axial direction. The moving end of the first shift fork 130 (1) in the second axial direction is changed from the reverse position to the reference position according to the rotation from the reverse position R to the parking position P of the drum member 140B. It has a groove shape.

Next, the groove shape of the first slider guide groove 144B (1) will be described.
The high-speed engagement portion 144B (1) H of the first slider guide groove 144B (1) is such that the first slider member 170 (1) presses the first shift fork 130 (1) toward the first side in the axial direction. In this state, the first shifter fork 130 (1) can move in the axial direction between the reference position restricted by the first fork guide groove 142B (1) and the first speed change position. 1) shows the movable range in the axial direction.

  Specifically, the first shift fork 130 (1) is positioned at the reference position, the high speed position, and the reverse position while the first slider member 170 (1) is in contact with the first stop portion 133 (1). In this case, the axial position where the first slider member 170 (1) is positioned is defined as a reference position, a first displacement position, and a second displacement position, respectively.

  In the present embodiment, as shown in FIG. 22, the high-speed engagement portion 144B (1) H of the first slider guide groove 144B (1) The first slider member 170 (1) is guided so as to be movable between the first displacement positions.

  The reverse engagement portion 144B (1) R is permitted by the reverse shift engagement portion 142B (1) R of the first shift fork guide groove 142B (1) when the drum member 140B is positioned at the reverse position R. The first slider member 170 (1) is fixed at a retracted position that does not limit the axial movement range of the first shift fork 130 (1).

  In the present embodiment, as shown in FIG. 22, the reverse slider engagement portion 144B (1) R of the first slider guide groove 144B (1) displaces the first slider member 170 (1) to the second displacement. It is configured to be fixed in position.

  That is, in the present embodiment, the first slider guide groove 144B (1) has the first slider member 170 (1) as the retracted position when the drum member 140B is positioned at the high speed position. It is comprised so that it may fix to two displacement positions.

In the present embodiment, the slider guide groove 144B (1) further has the following groove shape.
That is, as shown in FIG. 22, the neutral engagement portion 144B (1) N pushes the first slider engagement pin portion 174 (1) so as to fix the first slider member 170 (1) at the reference position. It has a groove shape to pinch.

  The transition portion between the neutral engagement portion 144B (1) N and the high speed engagement portion 144B (1) H is a reference position of the moving end of the first slider member 170 (1) toward the second side in the axial direction. The movement end of the first slider member 170 (1) in the first axial direction changes from the reference position to the first displacement position according to the rotation from the neutral position N to the high speed position H of the drum member 140B. It has a groove shape.

  The low speed engagement portion 144B (1) L has a groove shape that holds the first slider engagement pin portion 174 (1) so as to fix the first slider member 170 (1) at a reference position. Yes.

  The transition portion between the high-speed engagement portion 144B (1) H and the low-speed engagement portion 144B (1) L is the reference position of the moving end of the first slider member 170 (1) toward the second side in the axial direction. The movement end of the first slider member 170 (1) in the first axial direction is fixed from the first displacement position to the reference position in accordance with the rotation of the drum part 140B from the high speed position H to the low speed position L. It has a groove shape that can be changed.

  A transition portion between the neutral engagement portion 144B (1) N and the reverse engagement portion 144B (1) R is the first slider member 170 according to the rotation from the neutral position N to the reverse position R of the drum member 140B. It has a groove shape that guides (1) from the reference position to the second displacement position.

  The parking engaging portion 144B (1) P has a groove shape that holds the slider engaging pin portion 174 (1) so as to fix the first slider member 170 (1) at a reference position.

  The transition portion between the reverse engagement portion 144B (1) N and the parking engagement portion 144 (1) P is the first slider member 170 according to the rotation from the reverse position R to the parking position P of the drum member 140B. It has a groove shape that guides (1) from the second displacement position to the reference position.

Next, the groove shape of the second fork guide groove 142B (2) will be described.
The second fork guide groove 142B (2) is configured such that when the drum member 140B is positioned at the low speed position L, the second shift fork 130 (2) moves in the axial direction between the reference position and the low speed position. When the drum member 140B is positioned at the parking position P, the second shift fork 130 (2) is allowed to move in the axial direction between the reference position and the parking position, while the drum When the member 140B is positioned at the other operation position, it has a groove shape that fixes the second shift fork 130 (2) at the reference position.

  That is, as shown in FIG. 22, in the region from the high speed engagement portion 142B (2) H to the reverse travel engagement portion 142B (2) R, the second shift fork 130 (2) is fixed at the reference position. Thus, it has a groove shape that holds the second engagement pin portion 134 (2).

  On the other hand, in the low speed engagement portion 142B (2) L, the moving end of the second shift fork 130 (2) toward the first axial direction is the low speed position, and the moving end toward the second axial direction is the reference position. Thus, the groove has a groove shape for guiding the second engagement pin portion 134 (2).

  The transition portion between the high-speed engagement portion 142B (2) H and the low-speed engagement portion 142B (2) L is the movement end of the second shift fork 130 (2) toward the second side in the axial direction. While being fixed at the reference position, the moving end of the second shift fork 130 (2) in the first axial direction is changed from the reference position to the low speed position according to the rotation of the drum member 140B from the high speed position H to the low speed position L. It has such a groove shape.

  In the parking engagement portion 142B (2) P, the moving end of the second shift fork 130 (2) toward the first side in the axial direction becomes the reference position, and the moving end toward the second side in the axial direction becomes the parking position. Thus, it has a groove shape for guiding the second engagement pin portion 134 (2).

  A transition portion between the reverse engagement portion 142B (2) R and the parking engagement portion 142B (2) P is a movement end of the second shift fork 130 (2) toward the first side in the axial direction. While being fixed at the reference position, the moving end of the second shift fork 130 (2) in the second axial direction is changed from the reference position to the parking position according to the rotation of the drum member 140B from the reverse position R to the parking position P. It has such a groove shape.

Next, the groove shape of the second slider guide groove 144B (2) will be described.
The low-speed engagement portion 144B (2) L of the second slider guide groove 144B (2) has a low speed of the second shift fork guide groove 142B (2) when the drum member 140B is positioned at the low speed position L. The second slider member 170 (2) is fixed at a retracted position that does not limit the axial movement range of the second shift fork 130 (2) permitted by the hour engagement portion 142B (2) L.

  Specifically, the second shift fork 130 (2) is positioned at the reference position, the low speed position, and the parking position while the second slider member 170 (2) is kept in contact with the second stop portion 133 (2). In this case, the axial position where the second slider member 170 (2) is positioned is defined as a reference position, a third displacement position, and a fourth displacement position, respectively.

  In the present embodiment, as shown in FIG. 22, the low-speed engaging portion 144B (2) L of the second slider guide groove 144B (2) displaces the second slider member 170 (2) in the third displacement. It is configured to be fixed in position.

  That is, in the present embodiment, the second slider guide groove 144B (2) has the second slider member 170 (2) as the retracted position when the drum member 140B is positioned at the low speed position L. It is comprised so that it may fix to a 3rd displacement position.

  In the parking engagement portion 144B (2) P of the second slider guide groove 144B (2), the second slider member 170 (2) presses the second shift fork 130 (2) to the second side in the axial direction. In such a state, the second slider member 170 (2) is moved so that the second shift fork 130 (2) can move between the reference position and the parking position regulated by the second fork guide groove 142B (2). Describes the axially movable range.

  In the present embodiment, as shown in FIG. 22, the parking slider engaging portion 144B (2) P of the second slider guide groove 144B (2) has the second slider member 170 (2) at the reference position and the first position. The second slider member 170 (2) is guided so as to be movable between the four displacement positions.

  The drum-type transmission 1B having such a configuration can exhibit a standby action in a shifting operation.

First, the standby operation in the shifting operation to the high speed stage will be described.
When the drum member 140B is positioned at the neutral position N, as described above, the first shift fork 130 (1) and the second shift fork 130 (2) are fixed at the reference position ( (See FIG. 22).
Accordingly, the first and second shifter members 110 (1) and 110B (1) are both positioned at the reference position, and the drum-type transmission 1B is in a neutral state (see FIG. 21).

  When the drum member 140B is operated from the neutral position N to the high speed position H, as described above, the axial direction of the first shift fork 130 (1) regulated by the first fork guide groove 142B (1). The moving end on the first side changes from the reference position to the high speed position according to the rotation from the neutral position N to the high speed position H of the drum member 140B. The shift fork 130 (1) is movable in the axial direction between the reference position and the high speed position.

  As described above, the first slider member pushing spring 180 (1) (in this embodiment, the single spring 210) for biasing the first slider member 170 (1) toward the first axial direction is attached. Since the urging force is greater than the urging force of the first shift fork pushing spring 160 (1) that urges the first shift fork 130 (1) in the second axial direction, the drum member 140B When positioned at the high speed position H, the first shift fork 130 (1) and the first shifter member 170 (1) are moved from the first slider member pushing spring 180 (1) and the first shift fork. It will be in the state which can be moved to the high speed position of the axial direction 1st side with the urging | biasing force of the magnitude | size according to the difference of the urging | biasing force of the pushing spring 160 (1).

  Here, when the drum member 140B is positioned at the high speed position H, the relative position around the axis between the high speed uneven portion 112H of the first shifter member 110 (1) and the speed change uneven portion 12H of the transmission gear 10H. Is in a position where it can be engaged with unevenness, the unevenness portion for high speed 112H and the unevenness portion for shifting 12H are immediately engaged with unevenness and the transmission gear 10H is in a transmission state, so that the drum-type transmission 1B immediately becomes high speed. A step engagement state is established.

  On the other hand, when the convex part of the uneven part for high speed 112H of the first shifter member 110 (1) and the convex part of the uneven part for shifting 12H of the transmission gear 10H are brought into contact with each other, Only the drum member 140B can be rotated in advance to the high speed position H while the first shift fork 130 (1) and the first shifter member 110 (1) remain in the reference position.

  In the state in which the drum member 140B is rotated to the high speed position H, the first shift fork 130 (1) is axially movable between the reference position and the high speed position, and the first slider member 110 (1 ) Is movable in the axial direction between the reference position and the first displacement position.

  Accordingly, when the first shifter member 110 (1) and the transmission gear 10H rotate relative to each other around the axis and the butting of the convex portions is resolved, the first slider member pushing spring 180 (1) (main) In an embodiment, the single spring 210) and the first shift fork push spring 160 (1) are biased through the first shift fork 130 (1) by a biasing force having a magnitude corresponding to a difference in biasing force. The first shifter member 110 (1) is pushed to the high speed position and engages with the transmission gear 10H so that the shift operation to the high speed stage of the drum type transmission 1B is completed (standby action to the high speed stage). ).

  When the drum member 140B is positioned at the high speed position H, as described above, the second shift fork 130 (2) and the second shifter member 110B (2) are fixed at the reference position, The second shifter member 110B (2) is in a state in which neither the transmission gear 10L nor the transmission gear 10P is engaged with the concave and convex portions.

Next, the standby action in the shifting operation to the low speed stage will be described.
When the drum member 140B is positioned at the low speed position L, the first shift fork 130 (1) is fixed at the reference position, and the first shifter member 110 (1) is connected to both the high speed gear 10H and the reverse gear 10R. It will be in the state which does not engage with unevenness.

  On the other hand, the second shift fork 110 (2) is axially movable between the reference position and the low speed position, and the second slider member 110B (2) is in the retracted position (in this embodiment). The third displacement position is fixed.

  In this state, the urging force of the second slider member pushing spring 180 (2) does not act on the second shift fork 110 (2), and the second shift fork 110 (2) has the second force on the second shift fork 110 (2). Only the biasing force toward the second axial direction by the shift fork pushing spring 160 (2) acts.

  Accordingly, when the drum member 140B is positioned at the low speed position L, the second shift fork 130 (2) and the second shifter member 110B (2) are moved at a low speed by the second shift fork pushing spring 160 (2). It will be in the state which can be moved to a position.

  Here, when the drum member 140B is positioned at the low speed position L, the relative position around the axis between the low speed uneven portion 112L of the second shifter member 110B (2) and the speed change uneven portion 12L of the transmission gear 10L. , The low-speed concavo-convex portion 112L and the shift concavo-convex portion 12L immediately engage with the concavo-convex portion, and the transmission gear 10L enters the transmission state, so that the drum-type transmission 1B immediately becomes low-speed. A step engagement state is established.

  On the other hand, when the convex part of the uneven part for low speed and high speed 112L of the second shifter member 110B (2) and the convex part of the uneven part for shifting 12L of the transmission gear 10L are brought into contact with each other, While the second shift fork 130 (2) and the second shifter member 110B (2) are held at the reference position, only the drum member 140B is advanced to the low speed position L.

  Accordingly, when the second shifter member 110B (2) and the transmission gear 10L are relatively rotated about the axis and the abutment between the convex portions is eliminated, the second shift fork pushing spring 160 (2) is attached. The second shifter member 110B (2) is pushed to the low speed position by the force and engages with the transmission gear 10L so that the gear shift operation to the low speed stage of the drum type transmission 1B is completed (to the low speed stage). Standby action).

Next, the standby operation in the shifting operation to the reverse gear will be described.
When the drum member 140B is positioned at the reverse drive position R, the second shift fork 130 (2) is fixed at the reference position, and the second shifter member 110B (2) is connected to both the transmission gear 10L and the transmission gear 10P. It will be in the state which does not engage with unevenness.

  On the other hand, the first shift fork 130 (1) is in an axially movable state between a reference position and a reverse position, and the first slider member 110 (1) is in a retracted position (in the present embodiment, a first position). 2 displacement position).

  In this state, the biasing force of the first slider member pushing spring 180 (1) does not act on the first shift fork 130 (1), and the first shift fork 130 (1) has the first force. Only the biasing force toward the second axial direction by the shift fork pushing spring 160 (1) acts.

  Accordingly, when the drum member 140B is positioned at the reverse position R, the first shift fork 130 (1) and the first shifter member 110 (1) are moved backward by the first shift fork pushing spring 160 (1). It will be in the state which can be moved to a position.

  Here, when the drum member 140B is positioned at the reverse position R, the relative position around the axis between the reverse uneven portion 112R of the first shifter member 110 (1) and the shift uneven portion 12R of the transmission gear 10R. Is the position where the concave and convex portions can be engaged with each other, the reverse concave and convex portions 112R and the shift concave and convex portions 12R immediately engage with the concave and convex portions, and the transmission gear 10R is brought into a transmission state, so that the drum-type transmission 1B immediately reverses. A step engagement state is established.

  On the other hand, when the convex part of the reverse uneven part 112R of the first shifter member 110 (1) and the convex part of the convex part 12R for shifting of the transmission gear 10R are brought into contact with each other, While the first shift fork 130 (1) and the first shifter member 110 (1) are held at the reference position, only the drum member 140B is rotated forward to the reverse position R.

  Then, when the first shifter member 110 (1) and the transmission gear 10R rotate relative to each other about the axis and the abutment between the convex portions is eliminated, the first shift fork pushing spring 160 (1) is attached. The first shifter member 110 (1) is pushed to the reverse position by the force and engages with the transmission gear 10R, and the shift operation to the reverse speed of the drum type transmission 1B is completed (to the reverse speed). Standby action).

Finally, the standby action in the shifting operation to the parking stage will be described.
When the drum member 140B is positioned at the parking position P, the first shift fork 130 (1) is fixed at the reference position, and the first shifter member 110 (1) is connected to both the transmission gear 10H and the transmission gear 10R. It will be in the state which does not engage with unevenness.

  Meanwhile, the second shift fork 130 (2) is axially movable between the reference position and the parking position, and the second slider member 110B (2) is axially moved between the reference position and the fourth displacement position. The direction is movable.

  As described above, the second slider member pushing spring 180 (2) (in the present embodiment, the single spring 210) for biasing the second slider member 110B (2) toward the second axial direction is attached. Since the urging force is greater than the urging force of the second shift fork pushing spring 160 (2) that urges the second shift fork 130 (2) toward the first axial direction, the drum member 140B When positioned at the parking position P, the second shift fork 130 (2) and the second shifter member 110B (2) are moved to the second slider member pushing spring 180 (2) and the second shift fork. It becomes a state where it can be moved to the parking position on the second axial side with an urging force having a magnitude corresponding to the difference in the urging force of the push spring 160 (2).

  Here, when the drum member 140B is positioned at the parking position P, the relative position around the axis between the parking uneven portion 112P of the second shifter member 110B (2) and the shifting uneven portion 12P of the transmission gear 10P. , The parking uneven portion 112P and the shifting uneven portion 12P immediately engage with the concave and convex portions, and the drum type transmission 1B immediately enters the parking stage engaged state.

  On the other hand, when the convex part of the parking uneven part 112P of the second shifter member 110B (2) and the convex part of the shifting uneven part 12P of the transmission gear 10P are brought into contact with each other, Only the drum member 140B is advanced to the parking position P while the second shift fork 130 (2) and the second shifter member 110B (2) remain in the reference position.

  Then, when the second shifter member 110B (2) and the transmission gear 10P rotate relative to each other around the axis and the butting of the convex portions is eliminated, the second slider member pushing spring 180 (2) and the The second shifter member 110B (2) is pushed to the parking position by the biasing force having a magnitude corresponding to the difference in the biasing force of the second shift fork pushing spring 160 (2), and is engaged with the transmission gear 10P. Then, the shifting operation to the parking stage of the drum type transmission 1B is completed (standby operation to the parking stage).

  Thus, the drum-type transmission 1B according to the present embodiment can also have a standby action for all the gears including the parking gear.

  Further, the first boss portion 132 (1) of the first shift fork 130 (1) and the first boss portion 132 (2) of the second shift fork 130 (2) are movably supported. And the second slider members 170 (1) and 170 (2) and the first and second shift forks 130 (1) and 130 (2) are moved in the axial direction to bring out a standby action. Yes.

  Accordingly, the axial direction can be reduced in size and the operating force can be reduced as compared with the conventional configuration configured to obtain a standby action by moving the fork shaft in the axial direction.

  In the present embodiment, the first slider guide groove 144B (1) fixes the first slider member 110 (1) to a reference position when the drum member 140B is positioned at the neutral position N. When the drum member 140B is positioned at the high speed position H, the first slider member 110 (1) can be moved in the axial direction between the reference position and the first displacement position, and the drum member 140B is moved at the low speed position. The first slider member 110 (1) is fixed at a reference position when positioned at L, and the first slider member 110 (1) is fixed when the drum member 140B is positioned at a reverse position R. The first slider member 110 (1) is fixed at a reference position when the drum member 140B is positioned at the parking position P. The present invention is not limited to this aspect.

  For example, when the drum member 140B is positioned at the reverse position R, the first slider member 110 (1) is fixed at the retracted position (for example, the second displacement position), while the drum member 140B (1) is fixed. When positioned at a position other than the reverse position R, the first slider member 170 (1) biased toward the first axial direction by the first slider member pushing spring 180 (1) is the first slider member 170 (1). The first slider guide formed to allow the first shift fork 130 (1) to move in the axial direction following the movement in the axial direction while remaining in contact with the stop portion 133 (1). It is also possible to employ the groove 145B (1).

FIG. 23 is a development view of the drum member 140B including the first slider guide groove 145B (1).
As shown in FIG. 23, the reverse slider engagement portion 145B (1) R of the first slider guide groove 145B (1) fixes the first slider member 170 (1) to a retracted position (for example, a second displacement position). In addition, the neutral engagement portion 145B (1) N, the high speed engagement portion 145B (1) H, the low speed engagement portion 145B (1) L, and the parking engagement portion 145B (1) P One slider member 110 (1) has a groove shape that allows the slider member 110 (1) to move in the axial direction between the first displacement position and the second displacement position.

Further, the second slider guide groove 144B (2) is not limited to the groove shape in the present embodiment.
That is, in the present embodiment, the second slider guide groove 144B (2) is configured such that the second slider member 110B is located when the drum member 140B is positioned at the neutral position N, the high speed position H, and the reverse position R. (2) is fixed at the reference position, and when the drum member 140B is positioned at the low speed position L, the second slider member 110B (2) is fixed at the third displacement position, and the drum member 140B is positioned at the parking position. When positioned at P, the second slider member 110B (2) is configured to be axially movable between the reference position and the fourth displacement position.

  Instead, when the drum member 140B is positioned at the low speed position L, the second slider member 110B (2) is fixed at the retracted position (for example, the third displacement position), while the drum member 140B is fixed. When positioned at a position other than the low speed position L, the second slider member 170 (2) biased toward the second axial direction by the second slider member pushing spring 180 (2) is The second slider guide formed to allow the second shift fork 130 (2) to move in the axial direction following the movement in the axial direction while being in contact with the stop portion 133 (2). It is also possible to employ the groove 145B (2).

FIG. 23 shows the second slider guide groove 145B (2).
As shown in FIG. 23, the low-speed engagement portion 145B (2) of the second slider guide groove 145B (2) fixes the second slider member 110B (2) to a retracted position (for example, a third displacement position). Further, the other neutral engagement portion 145B (2) N, the high speed engagement portion 145B (2) H, the reverse engagement portion 145B (2) R, and the parking engagement portion 145B (2) P are the second ones. The slider member 110B (2) has a groove shape that allows the slider member 110B (2) to move in the axial direction between the third displacement position and the fourth displacement position.

10L transmission gear L (transmission gear)
10P Transmission gear P (parking gear) (parking member)
12L Convex / concave part for shifting 20L Transmission gear L (Transmission gear)
110 (2) Second shifter member (shifter member)
112L Uneven part for low speed (uneven part for shifting)
112P Uneven portion for parking 120 Fork shaft 130 (2) Second shift fork (shift fork)
140 Drum member 142 (2) Second fork guide groove (fork guide groove)
160 (2) Second shift fork pushing spring (shift fork pushing spring)
505 Oscillating axis 510 Parking operation arm 512 Boss part 514 Arm part 515 Engagement part 516 Pressure receiving surface 520 Parking release spring 530 Parking pushing member 532 Main body part 535 Cam pushing part 540 Parking coil spring 810 First transmission rotating shaft 820 Second transmission rotating shaft

Claims (8)

A transmission gear supported rotatably on the first transmission rotation shaft, a transmission gear supported non-rotatably on the second transmission rotation shaft and meshed directly or indirectly with the transmission gear, and an uneven portion for parking A parking member that is non-rotatable relative to the first or second transmission rotation shaft, a shifter member that is supported relative to the first transmission rotation shaft and is not rotatable relative to the first transmission rotation shaft, and a fork guide groove. A drum member that is rotated around an axis, a fork shaft that is parallel to the drum member, and is supported by the fork shaft so as to be movable in the axial direction, and the shifter member is axially moved according to its own axial movement. A shift fork that moves in a direction, and the shifter member and the transmission gear each have an uneven portion for shifting on opposite end surfaces thereof, and the fork plan according to the rotation of the drum member A drum-type transmission wherein the shifter member and the shift fork through the groove is moved in the axial direction together with the shifter member is concavo-convex engaging the speed change gear,
A parking operation arm having an engagement portion engageable with the parking uneven portion and capable of swinging about a swing axis parallel to the transmission rotation shaft, An operating arm for parking which can take a parking position in which an engaging part is engaged with the uneven part for parking and forcibly stops the rotation of the parking member;
A parking release spring that urges the operating arm for parking around the swing axis in a parking release direction that separates the engaging portion from the uneven portion for parking;
A parking pressing member having a main body portion supported by the drum member and a cam pressing portion extending radially outward from the main body portion;
The cam pushing portion does not act on the parking operation arm when the drum member is located at the neutral position and the shift position, and the cam pushing portion according to the rotation operation of the drum member to the parking position. A drum-type transmission, wherein the parking operation arm is pushed toward a parking position against a biasing force of a parking release spring. The main body is rotatably supported by the drum member, and is operatively connected to the drum member via a parking coil spring that is externally inserted into the drum member.
When the circumferential load applied to the cam pushing portion is a predetermined value or less, the parking coil spring integrally rotates the parking pushing member around the axis along with the rotation of the drum member around the axis. When the circumferential load applied to the cam pushing portion exceeds a predetermined value, the drum member is elastically deformed and the drum member rotates about the axis with respect to the parking pushing member. Configured to allow relative rotation in advance,
When the cam actuating portion swings the parking actuating arm toward the parking position, the engaging portion of the parking actuating arm is abutted against the convex portion of the parking gear concavo-convex portion, and the cam pushing operation is performed. When a circumferential load exceeding the predetermined value is applied to the part, the drum member rotates relative to the parking push member to the parking operation position while elastically deforming the parking coil spring, and the engaging part and At the stage where the circumferential position of the parking uneven portion is aligned, the holding elasticity of the parking coil spring resists the biasing force of the parking release spring and swings the parking operating arm to the parking position. The drum-type transmission according to claim 1, wherein the engagement between the mating portion and the parking uneven portion is completed. The operating arm for parking has a pressure receiving surface with which the cam pushing portion is engaged,
The direction of the reaction force received by the cam pusher from the pressure receiving surface when the cam pusher positions the parking operation arm at the parking position is determined based on the axis of the drum shaft. The drum-type transmission according to claim 1 or 2, wherein the portions substantially oppose each other in a direction extending radially outward.   The parking operation arm that is urged in the release direction around the swing axis by the parking release spring in a state in which the cam pushing portion does not act on the parking operation arm abuts on the fork shaft. The drum-type transmission according to any one of claims 1 to 3, wherein a swing end of the operating arm in the direction of releasing the swing axis is defined.   5. The drum-type transmission according to claim 1, wherein the shifter member has the parking uneven portion on an outer circumferential surface facing radially outward, and also functions as the parking member. .   5. The parking member according to claim 1, wherein the parking member is formed separately from the shifter member, and is formed by a parking gear that is supported on the first or second transmission rotating shaft so as not to be relatively rotatable. The drum-type transmission according to any one of the above. The operating arm for parking has a boss portion that is externally rotatably inserted on a pivot shaft that defines the swing axis, and has an engaging portion on a distal end side that extends radially outward from the boss portion. An arm portion,
The parking release spring has a coil spring externally attached to a boss portion of the parking operation arm,
The drum type transmission according to any one of claims 1 to 6, wherein one end side of the coil spring is locked to the pivot shaft and the other end side is locked to the parking operation arm. A shift fork pushing spring for urging the shift fork in a direction of pressing the shifter member against the transmission gear;
When the shift fork and the shifter member are positioned at the reference position and the shift position when the shifter member is not engaged with the shift gear and when the shift gear is engaged with the shift gear, respectively. The fork guide groove holds the shift fork at the reference position when the drum member is positioned at the neutral position and the parking position around the axis, and the drum member is positioned at the shift position around the axis. In any case, the shift fork has a groove shape for guiding the shift fork so that the shift fork can move in an axial direction between a reference position and a shift position. The drum-type transmission as described.

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